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By F. Bosché

Previous research has shown that ?Scan-vs-BIM? systems are powerful to provide valuable information for tracking structural works (progress, quality, safety). However, the transferability of this capability to other construction areas such as MEP works has not been assessed so far. Comparatively, the construction of MEP systems, in particular pipes and ducts, tends to be more flexible with respect to the positioning of individual components, so that Scan-vs-BIM systems could be defeated when tracking MEP installation works. This paper presents recent results on the feasibility and performance of using a Scan-vs- BIM system to track MEP works. The approach followed is presented and then tested with two real-life challenging case studies were conducted simultaneously but totally independently in Canada and Italy. The results show that, as expected, pipes and ducts tend to be more loosely positioned than structural elements leading to a poorer performance of the Scan-vs-BIM system. Nonetheless, it appears that the system works well to assess the level of conformance of site installation works, providing valuable information for estimating emerging performance metrics like ?percent built as-designed?. In addition, the proposed system could also be useful to accelerate and thus reduce the cost of delivering as-built BIM models for in the case of new builds.

Aug 1, 2013

By W. G. Worcester

Generally speaking, the term 'clay' appears to convey but little to the average layman other than of a sticky substance to be rigidly avoided when making a cross-country drive in the family ark- especially so if the chains have been left behind. On the other hand, the technical ceramic; engineer, though his chariot be bogged in the self-same mud-holes, will, more than likely, be planning on ways and means for the conversion of the troublesome gumbo into paving bricks over which all might ride with pleasure and security. However, to come to the point, the term 'clay' bears much the same relation to the ceramic world that the term 'ore' does to the metallurgical; in other words, as there are many kinds of ores, so also are there many kinds of clays, and it therefore becomes necessary to classify and sub-classify them previous to a discussion of their relative values and importance. Hence, a brief digression will be made from the main topic of this paper in order to enumerate and classify a number of the more important types of clays. By so doing, the relative position of Saskatchewan clays, later discussed, will be better understood.

Jan 1, 1929

By Brian W. Mackenkzie, Jozef Lajzerowicz

This paper is intended to familiarize planners in the noncommunist world with the district planning approach used in eastern Europe for mining development. It deals generally with the basic nature of the district planning problem, the planning process for mining development and the state organization for the planning of mining districts. A number of applications of district planning techniques to both established and new eastern European mining districts are described.

Jan 1, 1971

By Philippe Caudal

This paper presents a case study in which a slope failure was observed on the west wall of the LAB Chrysotile mine in the vicinity of the main ramp in January 2010. Airborne LiDAR results were used to evaluate slope geometry before and after the failure occurred. Back analysis of the failure was performed to assess rock mass properties at the slope scale using various numerical techniques: limit equilibrium, finite elements and fracture networks. The various approaches correlated well with field observations.

Aug 1, 2013

By M. Maleki-Moghaddam

At the concentration plant of the Gol-E-Gohar Iron Ore Company (Iran) three 9 m × 2.05 m AG mills (fixed speed) are used in parallel in a dry operation. The performance of AG mills has been lower than the target value indicated by an increase in the product size (P80) from 450 µm (target) to 515 µm and low power draw (50% of nominal). By simulation it was found that increasing the liner lifter face angle from 7 to 30o while keeping the original lifter height (i.e., 22.5 cm) could provide an appropriate charge trajectory. When the proposed liners installed in one of the AG mills, the throughput increased by 27%; when 5% (v/v) balls were added the throughput increased by 40%. The product size also decreased from 515 to 501 µm.

Jan 1, 2012

By Xiaozhu Chen, Qi Ping, Pu Yuan, Qinyong Ma

"In order to investigate the fractal feature of coalmine deep rock fragments under impact loads, variable cross-section split Hopkinson pressure bar apparatus, 50 mm in diameter, was adopted to conduct impact compressive test for rock specimens from -962m deep coalmine. Various impact pressures, such as 0.3, 0.6, 0.9 and 1.2MPa, were selected to implement different loading rates. Sieving statistical analyses were conducted for rock fragments after being impacted, and the particle size distribution of broken rock in various loading rates were calculated with the fractal method and then the corresponding fractal dimension was obtained. Test results shows that there is a good self-similarity and fractal feature in fragments distribution of deep coalmine sandstone under impact loads. The fractal dimension of fragments is between 1.9 and 2.7. The research also indicates that there is an approximate power relationship between dynamic compressive strength and fractal dimension, and a strength power relationship between fractal dimension and average strain rate. Moreover, there is a linear relationship between fractal dimension and specimen absorbed energy. The rock fractured process can be quantitatively described through fractal dimension, which can reflect the deep rock broken degree and is an ideal index to evaluate the distribution of rock fragments.INTRODUCTIONBroken rock is one of the most basic processes in mining operations, rock fragmentation has always been an important index to evaluate rock breaking effect (Xu & Yu, 1984). Macroscopic fragmentation of rock material is the final results of continuous development, expansion, gathering and cutthrough of internal micro-cracks. This process, developing from microscopic damage to macroscopic fragmentation, is an energy dissipation process and shows fractal characteristics (Xie, 1993). Turcotte (1986) has conducted statistical analyses of fragmentation for different kinds of geological materials under various broken conditions, and arrived at the conclusion that fragmentation distribution is a fractal."

Jan 1, 2015

By A. L. Mular

This paper provides a worthwhile contribution to the knowledge needed for calculating and using mathematical models of grinding circuits. The computer search algorithm proposed should remove much of the guesswork as well as reduce computer processing costs and improve the accuracy of estimated parameter values for grinding mill models.

Jan 1, 1970

By Deborah A. McCombe

"One of the cornerstones of NI43-101 Standards of Disclosure for Mineral Projects is the technical report. The purpose of the report is to provide a summary of the scientific and technical information concerning mineral exploration, development, and production activities on a mineral property that is material to an issuer. The reports must be prepared in accordance with NI43101 and Form 43-101F1 Technical Report and the information must be current as of the date of the filing of the technical report. As these reports provide important information to the investing public, qualified persons preparing these reports should, as much as possible, write in plain, simple language that can be easily read and understood by people who are not geoscientists or engineers. So let’s review some of the common deficiencies with technical reports. Non-current technical report Some of the factors you should consider when determining if your previously filed technical report is still current are as follows: •,Is there new technical information on the property, such as drilling, assays, metallurgical testwork? •,Have you made changes to key assumptions, parameters relating to mineral resources or mineral reserves, or economic analysis? If you have completed the previously recommended work, are your recommendations still current? Similarly, are your report recommendations consistent with what you are telling your shareholders or disclosing in the use of proceeds in your offering documents? For example, if the recommendations in the report consist of further exploration and metallurgical test-work prior to completing a preliminary feasibility study and you have completed the proposed work and are now raising money for a final feasibility study, the report is probably not current."

Jan 1, 2003

By L. V. Chugaev, Y. M. Shneerson, P. V. Zaytsev, I. V. Fomenko, M. A. Pleshkov

"Pressure oxidation (POX) is one of the most common and reliable methods of processing gold-bearing sulfide concentrates. However, when processing concentrates that contain natural carbonaceous matter, substantial gold losses occur due to autoclave preg-robbing. The latter involves formation of gold chloride complexes under typical POX conditions (high temperatures, high acidity and high ORP) and subsequent sorption of these complexes by carbonaceous matter. Naturally, chloride ion plays a significant role in the process of autoclave preg-robbing; its concentration in POX solution has a well-marked effect on subsequent gold recovery during cyanidation of POX residue. The previous research done by SRC Hydrometallurgy showed that autoclave preg-robbing of gold could be significantly inhibited by the addition of mercury(II) compounds to POX slurry. The positive effect of mercury(II) was well pronounced both at high (>20 mg/L) and low (<5 mg/L) Cl concentrations in POX solution. The successful bench-scale laboratory testing was followed by pilot plant trials at Ore Test Facility in Blagoveshchensk, Russia. The present paper provides the results of these trials. The bench-scale testing results were verified; the optimum oxidizing parameters and reagent dosage were specified. The behavior of mercury (II) at POX pilot plant was found to be in good consistency with industrial practice described in the literature.INTRODUCTION Pressure oxidation (POX) is one of the most common, reliable, and commercially proven methods of processing gold-bearing sulfide ores and concentrates. However, when processing double refractory materials that contain natural carbonaceous matter, POX technology advantages are compromised by autoclave preg-robbing of gold. The latter occurs when natural organic carbon and soluble halides are both present in autoclave feed. Strongly oxidizing conditions of POX (high temperature, oxidation-reduction potential or ORP, and acidity) favor formation of gold-halide (mostly, gold-chloride) complexes, which tend to bond with carbonaceous matter. The exact nature and mechanism of this bonding is unknown, but as the result of this, cyanide is unable to leach gold from POX residue and the precious metal is lost to the tails (Axenov et al., 2014; Dimov, Chryssoulis, & Sodhi, 2003; Fomenko, Zaytsev, Pleshkov, Chugaev, & Shneerson, 2013)."

Jan 1, 2017

By V. S. Papezik

Pyrophyllite, an AI silicate used in the production of ceramic materials, is formed mainly by alteration of felsic to intermediate volcanic rocks, either directly (at temperatures of 250-300°C and pressures of 1-2 kbar) or by subsequent low-grade metamorphism of aluminous protoliths produced by thermal fluids or even by prolonged weathering. Most pyrophyllite deposits in North America are concentrated in a belt of Late Precambrian volcanic and sedimentary rocks, the "Avalon Zone ", which extends along the eastern flank of the Appalachian mountain system from Newfoundland to the southeastern U.S.A. The only producing pyrophyllite mine in Canada is an open pit located near the settlement of Foxtrap on the Avalon Peninsula of Newfoundland. It lies in a belt of rhyolitic flows and pyroclastics intruded by a granitoid pluton. The rocks have been leached along a shear- or fracture zone, depleted in silica, alkalies, Ca, Mg and Fe by the action of hydrothermal fluids, and recrystallized to a very fine-grained massive assemblage of pyrophyllite, muscovite ("sericite") and quartz. High-grade pyrophyllite lenses contain small nodules of diaspore with minor barite; rutile is present in trace amounts. The close proximity of all pyrophyllitized zones on the peninsula to the granite contact suggests that the alteration was produced by thermal fluids genetically connected with the granitoid pluton. The fine-grained pyrophyllite-bearing rocks, with their simple mineralogy, are suitable for quantitative modal analysis by X-ray diffraction. Chemically analyzed samples from the alteration zone were used for the construction of working curves by plotting calculated mineral content against the intensity of selected diffraction peaks. The accuracy of the resulting curves is ±4.5% for quartz, ±3.6% for pyrophyllite and ±2.7% for muscovite. Pelletized samples give best results. The XRD method is suitable for a rapid analysis of a large number of grab or core samples to outline higher-grade areas for more detailed sampling.

Jan 1, 1978

By Dani J. Alldrick, Alastair J. Sinclair, Colin I. Godwin

"Abstract - The Stewart mining camp has a long history of precious and base metal mining. The camp is abundantly mineralized, with more than 200 widespread, varied, vein prospects, deposits and orebodies. These show wide variations in the mineralogy of ore, gangue and alteration assemblages, and wide variations in textures and structural settings. This report establishes the timing of the different metallogenic epochs and suggests a specific exploration application for systematic lead isotope analyses.Galena lead isotope ratios from a range of mineral occurrences indicate that all these varieddeposits formed during two main mineralizing events. Lead isotope data from the Stewart mining camp do not provide absolute ages for the formation of mineral deposits, but the relative distributions of data are consistent with dates determined in other studies. One ore-forming episode occurred in the Barly Jurassic and the other in the Middle Eocene. Both metallogenic epochs were brief, regional-scale phenomena. Sorne deposits from the younger mineralizing episode were em­ placed adjacent to or superimposed on the older deposits.Field and laboratory studies show that the two metallogenic epochs are characterized by different base and precious metal suites: Barly Jurassic gold-silver-zinc-lead-copper; and Middle Eocene silver-lead-zinc. Therefore, showings of different ages have different base and precious metal potentials and deserve different exploration emphasis. Lead isotope studies provide a reliable, cost-effective method for evaluating the age and commodity potential of small or recently discovered mineral showings and for setting exploration priorities on properties with several varied mineral occurrences . The determination of the age and metal potential of a prospect at an early stage of exploration may govern the urgency, intensity or even the necessity for further exploration work."

Jan 1, 1993

By Grant J. Goddard

"The Iron Ore Company of Canada (IOC) has been in operation for over 30 years. Today, and in the future, technology and its application will play an ever more critical role in the company’s business success.The Carol Mining and Concentrating (CMC) division of IOC is energetically applying technology today to enhance performance and results, and is aggressively exploring opportunities to apply technology to support improved business results in the future.A critical area of focus is the application of technology to maintenance management performance. CMC has taken a “back to basics” approach to the fundamentals of maintenance management in 1995 and 1996. In parallel, the mine is aggressively implementing its Vision 2000 maintenance integration plan. This plan is targeted at levering the energies applied to sound maintenance management fundamentals as the company moves to a fully condition based maintenance approach.This paper discusses some of the strategies, key technologies and objectives of theVision 2000 maintenance integration plan at the mining operations of IOC."

Jan 1, 1996

By K. Purazrang, P. Musavi Garavi, P. Sh. Naseri, P. Abachi

The fracture behavior of high strength Al7050 alloy was investigated at room and elevated temperatures using small size, V-notched tear (called Kahn specimen) and compact tension, CT, specimens, respectively.To study the elastic-plastic behavior of the alloy, the tensile test was also performed on the sub-sized cylindrical tension test specimen. The microstructure of the alloy was examined using optical- and scanning electron- microscopy. The rupture mechanisms and crack path were also studied by examination of specimens&apos; fracture surfaces using SEM. The microstructure examination revealed equiaxed grains and some elongated grains in rolling direction, with the areas of partial re-crystallized grains where coarse intermetallic particles are mostly found.In general, fracture surfaces were indicative of dimpled ductile type. Considering the fractographs of tensile specimens, the void growth mechanism is also dominant in fracture of these specimens. Nevertheless, in some regions, smooth areas can be observed due to the friction during rupture process. The results of mechanical tests at RT made the evaluation of tear strength to 0.2 % tensile yield strength ratio, as a measure of notch toughness, available. According to elevated temperature, 150°C, test results and plots of log da/dt vs. log KI , the crack propagation behavior over discrete ranges of crack growth rates could be assumed linear and then be obeyed as a power law equation in the form of da/dt = A (KI)n .

Jan 1, 2015

By C. T. Bischoff

Introduction Air conditioning is a term which has come into common use only during our generation. By definition, it means the positive and accurate control of temperature, humidity, movement, purity, and component constituents of the atmosphere within an enclosure. Claiming such results for Noranda&apos;s ventilation system, or for that of any other large mine, at present would be an idle boast. However, we are working toward that end with considerable success. Modern underground ventilation at Noranda dates back about six years. The later development of air conditioning is in its fourth season, but still in the experimental stage. Various ingenious methods have been devised to cool mines which, because of climatic or geological conditions or depth, are excessively warm. A few installations have been made to warm intake air during the winter months where this is necessary. However, the method currently in use at Noranda is unique in that it accomplishes both ends by one process. This method utilizes the freezing and melting of ice to equalize year-round temperatures. Mining Methods While a discussion of mining methods at Noranda is not proposed in this paper, a brief summary may be in order. The Horne mine of Noranda Mines, Limited, has been developed by six shafts, four of which are now active. The most recent, an internal shaft, extends to 6,000 feet below surface, but all of the ore mined to date has come from above the 3,000-foot level. Figure 1 shows a model of principal ore bodies. The area mined is relatively small in plan, considering its vertical extent and the tonnage per vertical foot. Most of the ore lies within an ellipse about 600 by 1,000 feet. While this has certain advantages, the mining of such massive orebodies has presented many problems.

Jan 1, 1947

By A. Galley, R. Tosdal, F. Robert

The Canada Mining Innovation Council (CMIC) Exploration Innovation Consortium developed a 10-year business case for developing new discovery criteria, exploration techniques, and better data management and analysis to improve exploration success in deep, remote, and covered terrains. Within this context, the CMIC devised a five-year project proposal to create improved multiparameter exploration tools to detect ore systems and more efficient vectoring toward high-grade mineralized cores. The Footprints project was approved March 2013. More than CAD$13 million funding was provided through the CMIC-led joint sponsorship from 30 companies and the Natural Sciences and Engineering Research Council. Consistent industry leadership and integration of dedicated industry and academic expertise has the project on track for reaching its well-defined objectives.

Jan 1, 2014

By Robb. V. M., F. Walraven, L. J. Robb

"Abstract -The old Albert Silver Mine is a polymetallic deposit comprising concentrations of Cu­ Pb-Zn-Ag-U-F within a set of sub-parallel quartz-hematite veins which occur within the fine-grained apical phase of the 2050 Ma old A-type Bushveld granites. Mineralization occurs as an early pyrite­ chalcopyrite-arsenopyrite-galena-sphalerite-(argentiferous) tetrahedrite paragenesis followed by a later, more oxidized assemblage comprising chlorite-hematite-fluorite-pitchblende. Accumulation of metals appears to have taken place at the interface between a coarse-grained porphyritic granite and an overlying fine-grained phase: veins occur in the latter and represent leakage of magmatic fluids from the differentiated, water-saturated, subjacent granite.Mineralization processes in the Bushveld granites are believed to be related to long-lived circulation of dominantly magmatic fluids stimulated by the high heat productive capacity of the host rocks. Endo- and exogranitic tin-tungsten and base metal mineralization formed during an evolving hydrothermal system that lasted for several hundred million years, forming innumerable small- to medium­ scale polymetallic deposits. At the Albert Silver Mine, unroofing of the cover sequences at circa 1600 Mato 1700 Ma resulted in the incursion of lower-temperature, high-f02 meteoric fluids which remobilized the earlier sulfides and introduced the paragenetically late U-F mineralization ."

Jan 1, 1994

By Alfred E. Pugsley

PAYMASTER CONSOLIDATED MINES, LIMITED, began an investigation into the economy and use of detachable bit drill-steel in June, 1937. This investigation has continued to the present time, and was made necessary by transportation and distribution difficulties that had arisen through the use of standard steel in three widely separated mine areas serviced by a central steel-sharpening shop. Detachable bit drill-steel performance was first studied in the workings of No. 2 mine, where the rock being drilled was composed mainly of porphyry or tourmaline, and where standard drill-steel transportation costs had been excessive. The results obtained in this early work definitely established the economy of detachable bit drill-steel at No. 2 mine. This conclusion was reached when the &apos;re-grind&apos; system of re-sharpening dulled detachable bits was 1n use. Preliminary observations on the performance of detachable bit drill-steel in the quartz-carbonate veins of No. S and No. 6 mines gave encouraging results, and warranted a large-scale investigation under practical mining conditions. All drilling operations were gradually changed over to use of detachable bit drill-steel. This change was completed by February, 1938.

Jan 1, 1939

By W. J. Adams

It is recognized that within life cycle assessment that the eco-toxicity potentials (TPs) derived for metals require additional research to improve their reliability. Current models used to develop TPs do not include important fate process for metals such as speciation and bioavailability. Toxicity potentials are standard values used in LCA to enable a comparison of potential toxic impacts between substances. Huijbrechts (2001) calculated toxicity potentials for 181 substances utilizing the USES model for six impact categories, i.e. freshwater aquatic ecotoxicity, marine aquatic ecotoxicity, freshwater sediment ecotoxicity, marine sediment ecotoxicity, terrestrial ecotoxicity and human toxicity (not considered here). Marine ecotox potential for metals is typically high using this approach, whereas most open ocean metal concentrations are very low. A sensitivity analysis of the USES-LCA model was undertaken using copper as an example. Results indicate: fate processes on the global scale are driving the marine water and sediment TPs for copper most; the second most important fate parameter is sedimentation from the water and burial in deep sediment layers; inclusion of speciation and bio-availability processes would be very beneficial; more accurate estimates of input parameters should be used, and the PNECwater and PNECsediment and all partition coefficients for metals should be updated in the model.

Jan 1, 2007

By M. H. Rana

"A survey of our knowledge in the field of rock mechanics is presented from the viewpoint of applications in the mining industry. Aspects of rock mechanics of special interest to the industry are enlarged upon, with emphasis on the avoidance of over-generalization. The relationship between fundamental and practical rock mechanics is discussed, and the need for cooperation between the university and industry to further our knowledge of -useful rock mechanics is emphasized. An attempt has been made to establish the scope of rock mechanics, as applied to problems in the mining industry. This is brought about by projecting rock mechanics as a tool to be intelligently used rather than magic, capable of producing ""miracles."" Continued education is important for individuals engaged in the application 0f rock mechanics in the mining industry. The scope of this education is discussed from a viewpoint of better communication between industry and the education and/or re-search establishments engaged in this work.Finally, the dangers of over-emphasis on rock mechanics are mentioned, but a justification of the in-vestment in rock mechanics programs in mines is also presented."

Jan 1, 1966

When underground extractions occur beneath or in close proximity to valleys and other forms of irregular surface topographic features, the observed vertical subsidence at the base of the valley is less than that would be expected in flat terrain, while the valley sides are observed to move inwards towards the centre of the valley. The reduction in subsidence at the bottom of the valley is referred to as upsidence and the convergence of two sides of the valley is termed valley closure. Research coupled with mining experience over the past few decades in Australia has identified valley closure subsidence as being very real and quite significant part of non-conventional subsidence effects, which always have adverse effects on natural features, with risks to water flow and aquatic ecosystems. In this paper, we describe a threedimensional numerical modelling approach to investigate the geomechanical mechanisms which cause the valley closure subsidence behaviour, using distinct element computer package 3DEC. The calibrated models can accurately predict subsidence and horizontal displacements, and they are subsequently extended to specifically study the effect of a series of mining geological and topographical factors on valley closure subsidence phenomenon, by developing a range of hypothetical scenarios. Previous analyses carried out using a two-dimensional numerical modelling technique have identified the potential parameters that affect the valley closure subsidence, which mainly include longwall position, horizontal stresses, valley sloping angle, and valley shape. Further three-dimensional analyses regarding the relationships between the major factors and valley closure subsidence are discussed in this paper. The results have significant implications with regard to both the underlying mechanisms that lead to this nonconventional subsidence behaviour, and how these should be incorporated in future valley closure subsidence prediction and mitigation of its impacts on natural features.

Jan 1, 2015